Apache2::Request / Upload Hook / HOOK_DATA

hi,

 I need to ask another question concerning Apache2::Request and the
 upload hook. Documentation says, that it's possible to pass custom
 data to the upload hook via HOOK_DATA parameter. Actually I noticed,
 that this feature seems to be disabled in Apache2::Request:

 Request.pm: sub hook_data {die "hook_data not implemented"}

 Every example I found at google was written for Apache::Request (not
 Apache2::Request) and so I'm a bit confused how to pass data to my
 upload kook. It seems that the only data passed to the upload
 callback is a APR::Request::Param object and the filedata from the
 buffer. I tried to find a way to get the Apache2::Request Object or
 Apache2::RequestRec Object with the APR::Request::Param object, but
 there's no backwards reference (I wanted to store data with
 $r->notes() method).

 Can you please explain to me, how communication with the upload hook
 is possible using Apache2::Request?

 Thanks in advice!

best regards,
Michael